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101.
At each low tide, male and female Uca tangeri remove mudballs from inside their burrows and place them on the surface. Previous studies have shown clear intersexual differences
in mudball arrangements. However, we noticed that some females placed their mudballs in an arrangement similar to that of
males. In this study, we investigated several factors that may have been responsible for this change in female mudballing
behavior. We found no significant effect of the lunar cycle, female size and reproductive state, or burrow features. We briefly
discuss the avoidance of sexual coercion or parasite modification of host behavior as possible factors. Our study shows that
intersexual differences in mudballing behavior are more complex than previously thought.
Received: October 18, 2000 / Accepted: May 7, 2001 相似文献
102.
S Krugmann K E Anderson S H Ridley N Risso A McGregor J Coadwell K Davidson A Eguinoa C D Ellson P Lipp M Manifava N Ktistakis G Painter J W Thuring M A Cooper Z-Y Lim A B Holmes S K Dove R H Michell A Grewal A Nazarian H Erdjument-Bromage P Tempst L R Stephens P T Hawkins 《Molecular cell》2002,9(1):95-108
We show that matrices carrying the tethered homologs of natural phosphoinositides can be used to capture and display multiple phosphoinositide binding proteins in cell and tissue extracts. We present the mass spectrometric identification of over 20 proteins isolated by this method, mostly from leukocyte extracts: they include known and novel proteins with established phosphoinositide binding domains and also known proteins with surprising and unusual phosphoinositide binding properties. One of the novel PtdIns(3,4,5)P3 binding proteins, ARAP3, has an unusual domain structure, including five predicted PH domains. We show that it is a specific PtdIns(3,4,5)P3/PtdIns(3,4)P2-stimulated Arf6 GAP both in vitro and in vivo, and both its Arf GAP and Rho GAP domains cooperate in mediating PI3K-dependent rearrangements in the cell cytoskeleton and cell shape. 相似文献
103.
104.
105.
Summary A total of 637 individuals from the rural village of Keneba in The Gambia, West Africa, have been typed for red cell PGM using isoelectric focusing (pH 5–7) in polyacrylamide gels. Eight different phenotypes have been detected. The frequency of the four alleles at the PGM1 locus was found to be PGM
1
1+
0.795, PGM
1
1-
0.053, PGM
1
2+
0.133, and PGM
1
2-
0.019. A study of the PGM phenotypes in 89 families confirmed the simple Mendelian codominant inheritance of the four alleles. Comparative population data suggest that red cell PGM typing by isoelectric focusing might prove to be a useful genetic marker in anthropological studies. 相似文献
106.
107.
Allogeneic restriction of acquired antimicrobial resistance was demonstrated by infusing Listeria-immune thoracic duct lymphocytes (TDL) into syngeneic, semisyngeneic, or allogeneic recipients that had been infected i.v. with Listeria monocytogenes (LM). Syngeneic and semisyngeneic recipients enjoyed a high level of protection (3 to 5 log10 reduction in viable organisms within 64 hr, whereas allogeneic recipients were poorly protected (0.5 to 2.5 log10 reduction). Sharing one haplotype between TDL-donors and challenged recipients resulted in a 4- to 8-fold increase in the level of resistance transferred. Histoincompatibility reactions could be excluded as a cause of the observed allogeneic restriction. Therefore, it is likely that LM-immune TDL are unable to respond efficiently to the antigens of this organism in an allogeneic environment. But allogeneic immune TDL do confer a low level of protection that cannot be ascribed to B cell activity nor to GvH and/or HvG reactions. Evidence is provided that the modest protection afforded by allogeneic lymphocytes is conveyed by the same T cell subset that operates with much higher efficiency in genetically related rats. 相似文献
108.
P A Flecknell T L Hooper G Fetherstony T J Locke C G McGregor 《Laboratory animals》1989,23(3):278-284
An anaesthetic regime was developed for lung transplantation in the dog using a continuous infusion of alfentanil and midazolam. This combination of agents provided excellent analgesia and also produced loss of consciousness. Cardiovascular stability was well maintained over a 24-h period of anaesthesia following lung transplantation. Although no animals were allowed to recover from anaesthesia in the present series, the regime described is likely to be suitable for recovery anaesthesia, particularly since both of the agents used can be reversed with specific antagonists. 相似文献
109.